Recently, electronic distribution systems have been widely recognized by general users or subscribers of portable telephones, so that melody sounds are downloaded and distributed to portable telephones as incoming call sounds over communication networks. In the future, it is expected that plenty of portable telephones provide musical tone playback circuits to play back musical tones of prescribed musical tunes that have rich expressions in music compared with simple incoming call sounds. For example, it is possible to develop portable telephones incorporating MP3 (namely, MPEG Audio Layer 3) decoders, to which MP3 data are distributed as audio contents. Thus, portable telephones incorporating MP3 decoders can be used as new music playback devices that substitute for the existing portable cassette tape players, for example.
It is naturally expected that users of portable telephones, which can be used as music playback devices, tend to regard musical tone playback functions important rather than original portable telephone functions. In addition, it is considered that users, particularly young users, may incline to listen to the music played back rather than human speech over phone communication. Such tendency will be increased in the future because all users do not always feel happy to receive phone calls at all times, in other words, some users may refuse to receive phone calls from unwelcome or undesirable persons with whom they do not want to communicate over the phones.
This invention is made in consideration of the aforementioned circumstances, so it is an object of the present invention to provide a portable telephone that is capable of controlling tone volume of played back musical tones and turning on or off playback of musical tones in response to the property of a calling party, which may be represented by calling party communication data automatically transmitted to a called party, such as the significance, priority, and personality of the calling party.